Most of Eurasia is either in or headed for population collapse within one to two decades. South America and Africa are picking up some of the slack but the UN has been predicting maximum world population at 9 billion in 2060 for decades. There probably are counter-trends but some trends were seen in the classical Greek dark age (roughly 900-600 BC) and the Western European dark age (400-800 AD) and are likely to be seen again. The lowest levels of decline will be seen in military, transport and communications technology. Roads, aqueducts, walls, tunnels and bridges are still in use 2-3 thousand years after construction. Since the US is not part of this population collapse most of the technological advances in Europe and the Far East will be outsourced here over the coming decade in much the same way that Byzantium and its outposts gained from the fall of Rome. Since US demographics have an economic boom baked in for 2025-30 and resuming after a slight dip in 2038-49 what form will that boom take?